Refrigerating apparatus for packaged goods



Feb. 21, 1933. R. R. BoT'roMs l REFRIGERATING APPARATUS FOR PACKAGEDGOODS Filed Sept. 11, 1930 INVENTOR I I I Wma myn,

0 RNEYJ Panna-d Fd. 21, 1933 y UN1TED STATES PATENT AOFI-lola ROBERTROGER BOTTOHS, OF LOUISVILLE, KENTUCKY, KBSIGNOB., BY HESNRASSIGN- m8,TO VOGT INSTANT FBEEZEBS INCORPORATED, OF IUISVILLE, KENTUCKY,

A. CORPORATION Ol' DELAWARE REIBIGEMTING .APPARATUS FORPACKAGED GOODSApplication med September 11, 1930. Serial No. 481,133.

This invention relates to the refrigerating of materials, and moreparticularly to a process and apparatus in which the materlals to berefrigerated are caused to pass through a body of liquid refrigerant.y

As one important feature lof my mvention I employ a refrigerant of acharacter which is either in gaseous form at atmosphenc pressure or hasa very high vapor pressure at such temperature. l

In order to permit of the use of a body of such refrigerant I provide asa further 1mportant feature means for maintaining the refrigerant in asealed chamber and provlde means whereby the articles to be frozen arepassed through a seal into said chamber and then through a seal out ofthe chamber so that none of the refrigerant will escape to theatmosphere.

My improved process and apparatus may be employed for the freezing ofvarious materials. If such materials be of such a character that theymight be injured in any way by direct contact with the refrlgerant fromthe seal, said materials are preferably enclosed in liquid ti htcontainers or packages. The packaging o the material to be frozen is notessential if such materials be of such character that they do not absorbeither sealing liquid or refrigerant and are not injured in ay way bycontact with the fluids employed in carrying out the process.

The refrigerant which I preferably employ is a liquefied petroleum oflow vapor pressure which will produce the refrlgerating action by itsown evaporation. It is advantageous to use propane as the refrigerant,although obviously the propane need not be pure and may have otheranalogous compounds associated therewith, as for instance, ethane,butane, etc.

For effecting the seal it is advantageous .to use a vliquid ,which isnot miscible with the refrigerant and which is not volatile to anyobjectionable extent at atmospheric pressure and the low temperatureemployed and which has no undesirable action on the materials to berefrigerated.

As an example of such sealing liquid I may employ ethyl alcohol if thetemperature of the refrigerant is not substantially below 40 F., but ifa lower temperature is to be employed, a suitable alcohol having a lowerfreezing point may b`e used-or ingredients added to the ethylalcoholwhichwill lower its freezing point. Y

It is preferable to use a refrigerant which will boil at or nearatmospheric pressure to produce the desired cooling effect.

As one important feature of my invention I `provide means forautomatically controlling the pressure in the refrigerant chamber so asto maintain a substantially constant temperature inasmuch as thetemperature of the boiling refrigerant will vary w1th its pressure.

In the accompanying drawing I have illustrated somewhat diagrammatlcallyan apparatus embodying my invention and adapted for carrying out myimproved process.

In these drawings Fig. 1 is a central vertical section of therefrigerant chamber and associated parts,

Fig. 2 is a side elevation of the apparatus shown in Fig. 1 togetherwith the additional pats going to make up a complete system, an

Fig. 3 is a transverse section on the line 3-3 of Fig. 1.

In the construction shown in Fig. 1 there is provided a refrigerantchamber 10 adapted to contain a volatile liquid refrigerant, such aspropane. The chamber is provided with suitable insulation 11 to reventheat losses and suitable means for mamtaining the liquid refrigerant ata substantially constant level and preferably enough below the top ofthe chamber to provide a gas space. For maintainin the level there isshown a supply pipe 12 lea 'ng to a float chamber 13 which communicateswith the refrigerant chamber through pipes 14 and 15 above and below thedesired liquid level so thatthere will be the same level in the floatchamber as in the refrigerating chamber. Within the float chamber is afloat 16 for operating a valve 17 and admitting refrigerant at such rateas to maintain the desired level.

In addition to the automatic float controlled valve 17 there ispreferably provided a manually controlled shut-of valve 18. The detailsof the float controlled valve form no rtion of m invention and have notbeen ilustrated in detail, but it will be evident that various wellknown and constructions of valve may be emp oyed for this purpose.

In connection with the valve 17 there .1s preferably a strainer forreventing a sol1d material from passing to e valve or interfering withits proper operation.

Eva rated refrigerant may be drawn off from thi; gas space of thechamber through a pipe 19 and opposite the inlet of this pipe there maybe provided a baille 20 for impeding the outflow of any unevaporatedentrained liquid refri rant.

. ber 10 has at the lower The refrigerant amber 10 adjacent to the lowerrtion is rovided with means for maintaining a sealing liquid and forpermitting the passage of the material to be refrigerated throu thesealin liquid into the refrigerating hquid. As ustrated the chamrtionthereof conduits 21 and 22 of such slze that the material to berefrigerated may be passed therethrough. T eseconduits both terminate atsuch 'an elevation that they may contain sufficient sealing liquid toprevent the escape of any of the refrigerant. .As illustrated theyterminate adjacent to the upper part of the refri rant chamber andcontain the sealing liquide 23. This li uid is of ater specific gravitythan the re rant hquid 24 and is not miscible therewit so that thesealing liquid is maintained at one level at vthe lower portion of therefrigerant chamber or in the adjacent portions of the conduits and ismaintained at a dierent level at the outer upper ends of the conduits.These levels will' var with the difference in the specic gravit of theliquids employed, the quantities of suc liquids, and the back pressurein the gas space of the refrigerant chamber.

For moving the material to be refrigerated into and out of therefrigerating chamber a suitable conveyor is employed. As illustratedthe refrigerant chamber'adjacent to the upper end thereof has Ytwo pairsof sprocket wheels 25 and 26 disposed above the inlet ends of the twoconduits 23 and 24. In the conduits are similar pairs of sprockets 27,28, 29 and 30 and above the outer ends of the conduits are similar pairsof sprockets 31 and 32. On approximatelythe same level as the rockets 31and32 is an additional pair 33.

o separate chains over these sprockets in succession and have connectedtherebetween suitable containers 34 for the material to be refrigerated.These containers 34 are preferably reticulated so that the refrigerantmay pass therethrough in contact with the material to be refrigerated orthe packages of the same and they are so suspended from the chains thatthey are held by gravity ip the same right side up position at allpoints of the path of travel.

The chains and receptacles 34 form substantially horizontal runs to andfrom the sprockets 33 so that an operator ma fill the containers orbaskets as t ey travel m the sprockets 33 to the sprockets 31 and mayremove the refrigerated products from the receptacles or baskets as theytravel along from sprockets -32 to the sprockets 33. Adjacent to thesehorizontal runs may be provided suitable loading latforms or otherapparatus to facilitate t e filling and emptying of the receptacles.

It will be noted thatas the receptacles am filled they pass the sprocket31 and thence down through the sealing liquid in the conduit 22, thencearound the sprockets and 29 and up out of the sealing hqpid and throughthe refri erating liquid. T is refrigerating liquid is ept at very lowtemperature by the proper control of t e back pressure, and if propanebe employed and the back pressure be in the neighborhood of atmosphericressure, the body of refrigerant liquid be at a temperature sutliclentto very rapidly freeze any water containing materials passedtherethrough.

The receptacles move across from the sprockets 25 to the sprockets 26,and thence .down through the refrigerating liquid and into the sealingliquid in the conduit 21. They then move around the sprockets 27 and 28and up out of the sealing liquid and around the sprockets 32 where theyemerge thoroughly frozen and ready for removal from the receptacles orbaskets.

4The conduit 21 for the outward movement of the material is preferablyinsulated both from the outside atmosphere and from the conduit 22, butthe conduit 22 need not be insulated from the wall of the refrigerantchamber as it is desirable that the liquid be cooled in order to precoolthe incoming material as it passes down the conduit 22 from thesprockets 31 to the sprockets 30. As shown the wall 35 between theconduit 22 and the refrigerant chamber is not insulated so that theremay be heat transfer through this wall and to facilitate the cooling ofthe sealing liquid in the conduit 22 there may be provided one or morepipes 36 along the outer side of the wall 35, and o ing into therefrigerant chamber at eir lower ends above the sealing liquid and attheir upper ends above the sealing liquid. Thus there will be an upllowof refrigerant in the conduits 36 due to heat absorptionfrom the sealingliquid and the gases resulting from the evaporation of this .refrigerantliquid will escape into the gas space of the refrigerant chamber.

Although -I have illustrated the refrigerant chamber as having twoseparate conduits 21 and 22 for the incoming and outgoingruns of theconveyors it will be obvious t at in some constructions the partitionbetween these conduits might be omitted and a single sealing chamberemployed.

I have illustrated a gauge glass 37 on the wall of the refrigerantchamber and communicating at its upper and lower ends with therefrigerant space and the sealing liquid space respectively so that thelevel between the two liquids may be readily observed and the amount ofrefrigerant maintained substantially constant.

Because of the low temperature of the refrigerant it is preferable thatthis gauge glass be of double wall type to prevent accumulation of frostand the obscuring of vision. In order to permit ready observation of thelevel of the dividing line between the tWo liquids the sealing liquidmaybe colored or the gauge glass may be so constructed that lightrefraction of the liquids of different `densities may be readilyobserved.

Obviously an increase in pressure in the chamber 10 will tend to lowerthe level of the sealing liquid, and it is desirable that thisthe limitsof the physical characteristics of A the refrigerant.

Any suitable means may be provided for operating the conveyor at thedesired speed in accordance with the desired extent of freezing. I haveillustrated somewhat diagrammatically a motor 38 which may beoperatively connected to the sprocket wheels 33 and may have its speedcontrolled at will.

In order to maintain the temperature of the refrigerant substantiallyconstant I employ means for maintaining the back pressure in therefrigerant chamber substantially constant. As illustrated there isprovided a refrigerating system including a compressor 40 adapted todeliver the compressed refrigerant gas through a conduit 41 and acondenser 42 to the inlet pipe 12./ The outlet pipe 19 leads from therefrigerant space back to thel compressor. The compressor is driven by asuitable prime mover, the speed of which is regulated by the amount ofback pressure in the refrigerating chamber. Merely as an example I haveshown a steam engine 43, in the steam supply 44 of which there isprovided a control valve 45. The valve is operated by a suitable plungerpiston or diaphragm in the chamber 46 and the opposite side of thisoperany decrease in pressure in the refrigerant 'i chamber will beautomatically restored to normal by aslowing down of the compressor.

Various other means might be employed for automatically controlling thecompressor 1n accordance with the back pressure in the refrigeratingchamber.

If the rate of delivery of the material or the temperature of thematerial delivered through the refrigerating chamber be such that thereis an abnormally rapid evaporation of the refrigerant, the increasedoutflow of gas through the pipe 19 may be employed for the control ofthe speed or volumetric displacement of the compressor.

Merely as an example of materials which may be frozen or refrigerated inmy improved apparatus and process I may mention fish, fruit andconfections. Such materials may be packed in liquid tight containerswhich have comparatively thin walls which permit rapid heat transfer orthey maybe wrapped in thin sheets of material such as cellophane or thelike. In using it for frozen confections, A

ice cream, sherbet or the like, the confection in its partially frozencondition as it comes from the freezer may be placed in liquid tightcontainers and the final hardening accomplished While passing throughthe chamber 10 instead of being placed in hardening rooms as is now theusual practice.

Having thus described my invention, what -I claim as new and desire tosecure by Letters Patent is:

1. A process of refrigerating material, which includes maintaining abody of volatile liquid refrigerant under a pressure permitting rapidevaporation, sealing said liquid from the outside atmosphere, andpassing the material to be refrigerated into and out of the refrigerantwithout permitting escape of the latter to the atmosphere.

2. A process of refrigerating materials, which includes maintaining abody of volatile liquid under a pressure permitting rapid evaporation,preventing escape of volatilized refrigerant to the atmosphere, andpassing the material to be refrigerated into and through therefrigerating liquid.

3. A process of refrigerating materials, which includes maintaining abody of volatile liquid under a pressure permitting rapid evaporation,maintaining a body of sealing liquid for preventing escape of saidrefrigerant to the atmosphere, passing the material to be refrigeratedthrough the sealing liquid and into the refrigerating liquid, andthereafter passin said material out through the sealing liq` 4. Aprocess of refrigerating material, which includes continuously advancingthe material through a sealing liquid, thence through a body of volatileliquid refrigerant, and then out through the sealing liquid.

5. A process of refrigeratin material, which includes maintaining a bo yof liquid propane under approximately atmospheric pressure whereby theliquid may rapidly evaporate at low temperature, passing the material tobe refrigerated throu h said liquid, and preventing the escape orefrigerant during the in movement and out movement of said material. Y

6. An apparatus for refrigerating material, which includes a refri erantchamber, means for delivering a volatile liquid refrigerant thereto,means for withdrawing vaorized refrigerant therefrom, a conveyor ormoving the material to be refrigerated linto and through said chamber incontact with said liquid, and means for controlling the pressure inysaid chamber to control the temperature to which the material issubjected.

7. An apparatus for refrigerating material, which includes a refrigerantchamber,

means for maintaining a volatile liquid refrigerant therein, a conveyorfor moving the material to be refrigerated into and through said liquid,and means for preventing the escape of refrigerant from said chamberduring the inward and outward movement of the material.

8. An a paratus for refrigerating material, inclu ing a refrigeratingchamber having inlet. and outlet openings, means -for maintaining avolatile liquid refrigerant therein at a substantially uniform level,seals at said openings and means for passing the material to berefrigerated through the seals and through the liquid refrigerant.

9. An apparatus for refrigerating material, including a refrigeratingchamber, means for maintaining a volatile liquid refrigerant therein ata substantially uniform level, a conveyor for moving the material to berefrigerated into and out of the liquid refrigerant and means forsealing the chamber at the points of entrance and exit of said conveyor.

10. An apparatus for refrigeratin material, including a refrigerating camber adapted to contain a volatile liquid refrigerant, a liquid sealcommunicating with the lower portion of said chamber, and an endlessconveyor extending through said liquid refrigerant and in and outthrough said liquid seal, and including containers for the material tobe refrigerated.

11. An apparatus for refrigerating material, including a refrigerantchamber having an inlet at the lower portion thereof, a seala conveyorextending through sai sea ing liquid and adapted to carry material intothe s here of action of said refrigerating liqui and means formaintaining the pressure within said chamber substantially constant.

13. A refrigerating apparatus including a refrigerating chamber having aconduit communicating therewith at the lower portion thereof and havingan upwardly extending outer end portion, a sealing liquid within saidconduit, a volatile liquid refrigerant within said chamber and sealedfrom the atmosphere by said liquid, means for maintaining the sealingliquid in said conduit at a low temperature, and means for deliveringthe material through said conduit and sealing liquid into saidrefrigerating liquid.

14. An apparatus for refrigerating material, including a refrigeratingchamber, means for delivering a volatile liquid refrigerant thereto,means for maintaining the level substantially constant in said chamber,means for maintaining the preure in said chamber substantially constant,a liquid seal to said chamber, means for maintaining the liquid in saidseal at a low temperature, and means for passing the material to berefrigerated through said liquid seal into said liquid refigerant andback out through said liquid sea 15. A refrigerating apparatus includinga refrigerating chamber, means for maintaining a volatile 1i uidrefrigerant therein, means for with rawing refrigf rant gas therefrom,means for automatically varying the rate of withdrawal of gas tomaintain the pressure substantially constant, a conveyor having a seriesof receptacles, means for moving said conveyor into and out of saidchamber, and means for preventing the escape of liquid refrigerantduring the movement of said conveyor.

16. A refrigerating apparatus including a refrigerating chamber, meansfor maintaining a volatile liquid refrigerant therein, means forwithdrawing refrigerant gas therefrom, means for automatically varyingthe rate of withdrawal of gas to maintain the pressure substantiallyconstant, a conveyor having a series of receptacles, means for movingsaid conveyor into and out of said chamber, and a liquid sealcommunicating with said receptacles and through which said conveyorextends.

17. The process of refrigerating material, including advancing thematerial into, through and out of a chamber, continuously deliverinvolatile refrigerant in liquid form to said c amber for direct contactwith the material or the wrapping or container thereof, and withdrawingsaid refrigerant in gaseous form from said chamber.

18. The process of refrigerating material, including advancing thematerial into,

through and out of a chamber, maintaining a substantially constantamount of refrigerant in liquid form in said chamber for direct contactwith the material or the wrapping or container thereof, withdrawing saidrefrigerant in gaseous form from said chamber, and substantiallypreventing the escape of refrigerant from said chamber or the entranceof air to said chamber at the points of entrance and exit of thematerial.

19. The process of refrigerating material, which includes circulating avolatile refrig` erant through a closed cycle including compressing therefrigerant vapor, cooling and liquefying the same, and vaporizing theliquid under reduced pressure, maintaining a substantially constantamount of said liquid at the point in the cycle where saidva orizing iseffected, and passing the materlal to be refrigerated into, through andout of the vaporizing liquid.

20. The process of refrigerating material, which includes circulating avolatile refrigerant through a closed cycle including compressing therefrigerant vapor, cooling and liquefylng the same, and vaporizing theliquid under reduced pressure, passing the material to be refrigeratedinto, through and out of the vaporizing liquid, and preventingintermixing of the refrigerant and the at mosphere at the point ofentrance of the material to the chamber and the point of exit of thematerial therefrom.

Signed at New York in the county of. New York and State of New York this9th day of September A. D. 1930.

ROBERT ROGER BOTTOMS.

